/* ===================================================================
   Microbiology — shared stylesheet
   MedStudy · TMU MBBS Year 2 Semester 1
   Accent: --ra #047857 (emerald) — the colour reserved for this subject
   in the Immunology notes. All six Year-2 subjects are now visually
   separable: anatomy sienna · biochemistry indigo · immunology rose ·
   intro-to-medicine slate · microbiology emerald.
   NOTE: the variable is still named --ra so the shared component classes
   can be reused verbatim. Only the colour differs.
   =================================================================== */

:root{
  --ra:      #047857;   --ra-lt:  #ecfdf5;   --ra-md: #059669;
  --blue:    #1a3a5c;   --blue-lt:#eaf1fb;
  --red:     #c0392b;   --red-lt: #fdf2f2;
  --gold:    #b8860b;   --gold-lt:#fffde7;
  --green:   #1a6b3c;   --green-lt:#f0faf4;
  --purple:  #5b2d8e;   --purple-lt:#f3eefb;
  --grey:    #4a4a4a;   --grey-lt:#f5f5f5;
  --border:  #d7e6de;   --shadow: 0 2px 12px rgba(0,0,0,.09);
}
*{box-sizing:border-box;margin:0;padding:0}
body{font-family:'Segoe UI',Arial,sans-serif;background:#f2f3f9;color:#222;font-size:15.5px;line-height:1.75}

/* ---------- TOP BAR ---------- */
.topbar{background:var(--ra);color:#fff;padding:0 28px;display:flex;align-items:center;justify-content:space-between;height:54px;position:sticky;top:0;z-index:100;box-shadow:0 2px 8px rgba(0,0,0,.3)}
.topbar .breadcrumb{font-size:12px;opacity:.75}
.topbar .unit-title{font-size:17px;font-weight:700;letter-spacing:.3px}
.topbar .badge{background:#fff;color:var(--ra);border-radius:4px;padding:2px 8px;font-size:11px;font-weight:700;letter-spacing:.5px}
.topbar-right{display:flex;align-items:center;gap:8px}
.tb-btn{background:rgba(255,255,255,.18);border:1px solid rgba(255,255,255,.32);color:#fff;padding:5px 13px;border-radius:6px;font-size:12px;font-weight:700;text-decoration:none;white-space:nowrap;transition:.15s}
.tb-btn:hover{background:rgba(255,255,255,.32)}
.tb-btn.qbank{background:rgba(255,255,255,.3);border-color:rgba(255,255,255,.55)}
.tb-btn.home{background:rgba(0,0,0,.16)}

/* ---------- LAYOUT ---------- */
.layout{display:flex;max-width:1320px;margin:0 auto;padding:24px 16px;gap:24px}
.main{flex:1;min-width:0}

/* ---------- SIDEBAR ---------- */
.sidebar{width:236px;flex-shrink:0;position:sticky;top:78px;height:fit-content}
.sidebar-box{background:#fff;border-radius:10px;box-shadow:var(--shadow);overflow:hidden}
.sidebar-header{background:var(--ra);color:#fff;padding:10px 16px;font-size:12px;font-weight:700;letter-spacing:.8px;text-transform:uppercase}
.sidebar nav a{display:block;padding:9px 16px;font-size:13px;color:var(--grey);text-decoration:none;border-left:3px solid transparent;border-bottom:1px solid #eef0f7;transition:all .15s}
.sidebar nav a:hover,.sidebar nav a.active{background:var(--ra-lt);border-left-color:var(--ra);color:var(--ra);font-weight:600}
.sidebar nav a.sub{padding-left:28px;font-size:12.5px;color:#666}
.exam-badge-box{margin-top:14px;background:#fff;border-radius:10px;box-shadow:var(--shadow);padding:14px 16px}
.exam-badge-box h4{font-size:11px;font-weight:700;letter-spacing:.8px;text-transform:uppercase;color:var(--ra);margin-bottom:8px}
.exam-badge-box .pill{display:inline-block;background:var(--ra-lt);border:1px solid #a7f3d0;color:var(--ra);border-radius:4px;padding:3px 8px;font-size:11.5px;margin:2px 2px 2px 0}

/* ---------- UNIT HERO ---------- */
.unit-hero{background:linear-gradient(135deg,#064e3b 0%,#059669 100%);border-radius:12px;padding:28px 32px;color:#fff;margin-bottom:24px;box-shadow:var(--shadow)}
.unit-hero .unit-num{font-size:11px;font-weight:700;letter-spacing:1.5px;text-transform:uppercase;opacity:.75;margin-bottom:6px}
.unit-hero h1{font-size:26px;font-weight:800;margin-bottom:10px}
.unit-hero .meta{font-size:12.5px;opacity:.85;line-height:1.9}
.unit-hero .meta span{display:inline-block;background:rgba(255,255,255,.15);border-radius:4px;padding:2px 8px;margin:2px 4px 2px 0}

/* ---------- SECTION CARDS ---------- */
.section-card{background:#fff;border-radius:10px;box-shadow:var(--shadow);margin-bottom:24px;overflow:hidden}
.section-header{padding:14px 24px;border-bottom:2px solid var(--border);display:flex;align-items:center;gap:12px}
.section-header .section-num{background:var(--ra);color:#fff;border-radius:6px;padding:3px 10px;font-size:12px;font-weight:700}
.section-header h2{font-size:17px;font-weight:700;color:var(--ra)}
.section-body{padding:22px 24px}

.subtopic{margin-bottom:36px;padding-bottom:28px;border-bottom:1px dashed #e6ded8}
.subtopic:last-child{border-bottom:none;margin-bottom:0;padding-bottom:0}
.subtopic-title{font-size:15.5px;font-weight:700;color:var(--ra);margin-bottom:16px;display:flex;align-items:center;gap:8px}
.subtopic-title .star{color:#e67e22;font-size:16px}

.micro{margin-bottom:14px}
.micro-label{font-size:11px;font-weight:700;letter-spacing:.9px;text-transform:uppercase;color:#7b7b95;margin-bottom:5px;padding-left:10px;border-left:3px solid var(--border)}
.micro-body{font-size:15px;color:#333;line-height:1.8}

/* teaching prose */
p.teach{margin-bottom:13px;line-height:1.85;font-size:15px;color:#333}
p.teach + p.teach{margin-top:0}

/* ---------- SPECIAL BOXES ---------- */
.box-definition{background:var(--ra-lt);border-left:4px solid var(--ra);border-radius:0 8px 8px 0;padding:14px 18px;margin-bottom:16px}
.box-definition .label{font-size:10.5px;font-weight:700;letter-spacing:1px;text-transform:uppercase;color:var(--ra);margin-bottom:5px}
.box-definition p{font-size:15px;color:#312e81;line-height:1.8}
.box-definition .exam-tag{display:inline-block;background:var(--ra);color:#fff;border-radius:4px;padding:1px 7px;font-size:10px;font-weight:700;margin-left:6px;letter-spacing:.4px;vertical-align:middle}

.box-clinical{background:var(--red-lt);border-left:4px solid var(--red);border-radius:0 8px 8px 0;padding:14px 18px;margin-bottom:16px}
.box-clinical .label{font-size:10.5px;font-weight:700;letter-spacing:1px;text-transform:uppercase;color:var(--red);margin-bottom:5px;display:flex;align-items:center;gap:5px}
.box-clinical p{font-size:14.5px;color:#4a1010;line-height:1.8}

.box-exam{background:var(--gold-lt);border-left:4px solid var(--gold);border-radius:0 8px 8px 0;padding:14px 18px;margin-bottom:16px}
.box-exam .label{font-size:10.5px;font-weight:700;letter-spacing:1px;text-transform:uppercase;color:var(--gold);margin-bottom:10px;display:flex;align-items:center;gap:5px}
.qa-pair{margin-bottom:12px;padding:10px 14px;background:rgba(255,255,255,.72);border-radius:6px;border:1px solid #f0e0a0}
.qa-q{font-size:14px;font-weight:600;color:#5a4500;margin-bottom:5px}
.qa-a{font-size:14px;color:#3a3000;line-height:1.7}
.qa-source{font-size:11px;color:#a08020;font-style:italic;margin-top:3px}

.box-mnemonic{background:var(--green-lt);border-left:4px solid var(--green);border-radius:0 8px 8px 0;padding:14px 18px;margin-bottom:16px}
.box-mnemonic .label{font-size:10.5px;font-weight:700;letter-spacing:1px;text-transform:uppercase;color:var(--green);margin-bottom:8px}
.box-mnemonic p{font-size:14.5px;color:#0d3d22;line-height:1.8}

.box-intuition{background:#eef6ff;border-left:4px solid #2563eb;border-radius:0 8px 8px 0;padding:14px 18px;margin-bottom:16px}
.box-intuition .label{font-size:10.5px;font-weight:700;letter-spacing:1px;text-transform:uppercase;color:#1d4ed8;margin-bottom:6px}
.box-intuition p{font-size:14.5px;color:#16305c;line-height:1.8}

.box-dissect{background:var(--purple-lt);border-left:4px solid var(--purple);border-radius:0 8px 8px 0;padding:14px 18px;margin-bottom:16px}
.box-dissect .label{font-size:10.5px;font-weight:700;letter-spacing:1px;text-transform:uppercase;color:var(--purple);margin-bottom:6px}
.box-dissect p,.box-dissect li{font-size:14.5px;color:#2e1a4a;line-height:1.8}
.box-dissect ol{padding-left:20px}

/* ---------- LISTS & TABLES ---------- */
.components-list{counter-reset:comp;margin:8px 0}
.components-list li{list-style:none;counter-increment:comp;padding:8px 14px 8px 44px;position:relative;background:var(--grey-lt);border-radius:6px;margin-bottom:6px;font-size:14.5px;line-height:1.7}
.components-list li::before{content:counter(comp);position:absolute;left:12px;top:8px;background:var(--ra);color:#fff;width:22px;height:22px;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:12px;font-weight:700}
.components-list li strong{color:var(--ra)}

.table-wrap{overflow-x:auto;margin:12px 0}
.data-table{width:100%;border-collapse:collapse;font-size:14px;margin:12px 0}
.data-table th{background:var(--ra);color:#fff;padding:10px 14px;text-align:left;font-size:12.5px;font-weight:600}
.data-table td{padding:10px 14px;border-bottom:1px solid var(--border);vertical-align:top;line-height:1.6}
.data-table tr:nth-child(even) td{background:var(--grey-lt)}
.data-table tr:hover td{background:var(--ra-lt)}

/* ---------- IMAGES ---------- */
.img-wrap{margin:18px 0;text-align:center}
.img-wrap img{max-width:100%;border-radius:8px;box-shadow:0 3px 16px rgba(0,0,0,.15);border:1px solid var(--border);cursor:zoom-in;transition:transform .2s}
.img-wrap img:hover{transform:scale(1.02)}
.img-caption{font-size:12px;color:#666;margin-top:7px;font-style:italic}
.img-source{font-size:11px;color:#999}
.img-row{display:flex;gap:16px;margin:18px 0}
.img-row .img-wrap{flex:1;margin:0}
.lightbox{display:none;position:fixed;inset:0;background:rgba(0,0,0,.9);z-index:999;justify-content:center;align-items:center}
.lightbox.open{display:flex}
.lightbox img{max-width:92vw;max-height:90vh;border-radius:8px;box-shadow:0 0 40px rgba(0,0,0,.6)}
.lightbox-close{position:absolute;top:18px;right:24px;color:#fff;font-size:32px;cursor:pointer;background:none;border:none;line-height:1}

/* ---------- ACTIVE RECALL ---------- */
.recall{background:#111132;color:#e6e6f5;border-radius:8px;padding:14px 18px;margin:18px 0;font-size:13.5px;line-height:1.7}
.recall .recall-label{font-size:10.5px;font-weight:700;letter-spacing:1px;text-transform:uppercase;color:#a5b4fc;margin-bottom:6px;display:block}
.recall ul{padding-left:18px;margin-top:6px}
.recall ul li{margin-bottom:5px}

/* ---------- Q-BANK ---------- */
.qbank-section{background:#fff;border-radius:10px;box-shadow:var(--shadow);margin-bottom:24px;overflow:hidden}
.qbank-header{padding:14px 24px;display:flex;align-items:center;gap:12px;border-bottom:2px solid var(--border)}
.qbank-header h2{font-size:17px;font-weight:700;color:var(--ra)}
.qbank-tab-bar{display:flex;border-bottom:2px solid var(--border);flex-wrap:wrap}
.qbank-tab{padding:10px 22px;font-size:13px;font-weight:600;cursor:pointer;border:none;background:none;color:#7b7b95;border-bottom:3px solid transparent;margin-bottom:-2px;transition:all .15s}
.qbank-tab.active{color:var(--ra);border-bottom-color:var(--ra);background:var(--ra-lt)}
.qbank-pane{display:none;padding:20px 24px}
.qbank-pane.active{display:block}

.mcq-item{border:1px solid var(--border);border-radius:8px;margin-bottom:12px;overflow:hidden}
.mcq-q{padding:12px 16px;background:#fafaff;font-size:14.5px;font-weight:600;color:#1a1a1a;border-bottom:1px solid var(--border);display:flex;gap:10px}
.mcq-num{background:var(--ra);color:#fff;border-radius:4px;padding:1px 8px;font-size:12px;font-weight:700;white-space:nowrap;align-self:flex-start;margin-top:1px}
.mcq-options{padding:10px 16px;display:grid;grid-template-columns:1fr 1fr;gap:4px 16px}
.mcq-opt{font-size:13.5px;padding:4px 6px;border-radius:4px;color:#444}
.mcq-opt.correct{background:#d4edda;color:#155724;font-weight:700}
.mcq-reveal{display:none;padding:10px 16px;border-top:1px solid var(--border);background:var(--ra-lt);font-size:13.5px;line-height:1.7}
.mcq-reveal .ans-label{font-size:10px;font-weight:700;letter-spacing:1px;text-transform:uppercase;color:var(--ra);margin-bottom:3px}
.mcq-reveal .reason{color:#312e81}
.mcq-btn{display:block;width:100%;text-align:center;padding:7px;background:none;border:none;border-top:1px solid var(--border);font-size:12px;color:var(--ra);cursor:pointer;font-weight:600}
.mcq-btn:hover{background:var(--ra-lt)}
.src-tag{display:block;font-size:11px;color:#8f8fae;font-style:italic;margin-top:5px}

.def-item{border:1px solid var(--border);border-radius:8px;margin-bottom:10px;overflow:hidden}
.def-q{padding:11px 16px;background:#fafaff;font-size:14.5px;font-weight:600;color:#1a1a1a;display:flex;justify-content:space-between;align-items:center;cursor:pointer;gap:12px}
.def-q:hover{background:var(--ra-lt)}
.def-num{background:var(--ra);color:#fff;border-radius:4px;padding:1px 7px;font-size:11px;font-weight:700;white-space:nowrap}
.def-toggle{font-size:18px;color:var(--ra);font-weight:300;line-height:1}
.def-answer{display:none;padding:12px 16px;border-top:1px solid var(--border);font-size:14px;line-height:1.8;color:#333;background:#fff}
.def-marks{font-size:10px;color:#aaa;font-weight:400;margin-left:6px}

.essay-item{border:1px solid var(--border);border-radius:8px;margin-bottom:14px;overflow:hidden}
.essay-q{padding:13px 16px;background:#fafaff;cursor:pointer;border-bottom:1px solid var(--border);display:flex;gap:10px;align-items:flex-start}
.essay-q:hover{background:var(--gold-lt)}
.essay-num{background:var(--gold);color:#fff;border-radius:4px;padding:2px 8px;font-size:11px;font-weight:700;white-space:nowrap}
.essay-qtext{font-size:14.5px;font-weight:600;color:#1a1a1a;flex:1}
.essay-marks{background:var(--ra);color:#fff;border-radius:4px;padding:2px 8px;font-size:11px;font-weight:700;white-space:nowrap}
.essay-answer{display:none;padding:16px;font-size:14px;line-height:1.85;color:#333}
.essay-answer h4{color:var(--ra);font-size:13px;font-weight:700;text-transform:uppercase;letter-spacing:.5px;margin:14px 0 6px}
.essay-answer p{margin-bottom:10px}
.essay-answer ul,.essay-answer ol{padding-left:20px;margin-bottom:10px}
.essay-answer li{margin-bottom:4px}
.marking{background:var(--gold-lt);border:1px solid #f0e0a0;border-radius:6px;padding:10px 14px;margin-top:12px;font-size:13px}
.marking strong{color:var(--gold)}

/* ---------- STICKY BOTTOM BAR (qbank) ---------- */
.back-footer{position:sticky;bottom:0;background:#fff;border-top:2px solid var(--border);padding:10px 24px;display:flex;gap:10px;justify-content:center;box-shadow:0 -2px 10px rgba(0,0,0,.06);z-index:60}
.back-footer a{background:var(--ra-lt);color:var(--ra);border:1px solid #a7f3d0;padding:7px 16px;border-radius:6px;font-size:13px;font-weight:600;text-decoration:none;transition:.15s}
.back-footer a:hover{background:var(--ra);color:#fff}
.back-footer a.home{background:var(--ra);color:#fff}

/* ---------- FOOTER + MISC ---------- */
.page-footer{text-align:center;padding:22px;font-size:.78rem;color:#666;border-top:1px solid var(--border);margin-top:30px}
.page-footer a{color:var(--ra);text-decoration:none;font-weight:600}
.scroll-top{position:fixed;bottom:28px;right:28px;background:var(--ra);color:#fff;border:none;border-radius:50%;width:44px;height:44px;font-size:20px;cursor:pointer;box-shadow:var(--shadow);display:flex;align-items:center;justify-content:center;z-index:50}
.scroll-top:hover{background:var(--ra-md)}

@media (max-width:900px){
  .sidebar{display:none}
  .img-row{flex-direction:column}
  .mcq-options{grid-template-columns:1fr}
  .topbar{padding:0 14px;gap:10px}
  .topbar > div:first-child{min-width:0;flex:1}
  .topbar .unit-title{font-size:14px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
  .topbar .breadcrumb{white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
  .topbar .badge{display:none}
  .topbar-right{flex-shrink:0}
  .unit-hero{padding:20px 18px}
  .unit-hero h1{font-size:20px}
  .section-body{padding:16px 14px}
}

/* ===================================================================
   Immunology-only Q-Bank components
   The TMU paper has two formats no other subject uses: fill-in-the-
   blanks (Section II, 20% of the paper) and true/false (Section IV,
   12%). Together they are nearly a third of the mark, so they get
   first-class runners rather than being folded into the MCQ list.
   =================================================================== */

/* --- fill in the blanks --- */
.blank-item{background:#fff;border:1px solid var(--border);border-radius:9px;padding:16px 18px;margin-bottom:14px}
.blank-q{display:flex;gap:10px;align-items:flex-start;font-size:14px;line-height:2.1;color:#222}
.blank-text{flex:1}
.blank-marks{font-size:11px;font-weight:700;color:#999;white-space:nowrap;padding-top:4px}
.blank{display:inline-block;min-width:82px;text-align:center;border-bottom:2px solid var(--ra);
  background:var(--ra-lt);border-radius:3px 3px 0 0;padding:1px 8px;margin:0 3px;
  font-weight:700;color:#bbb;transition:color .2s,background .2s}
.blank.filled{color:var(--ra);background:#ffe4e9}
.blank-reveal{display:none;margin-top:12px;padding-top:12px;border-top:1px dashed var(--border);font-size:13px;line-height:1.75;color:#444}

/* --- true / false --- */
.tf-item{background:#fff;border:1px solid var(--border);border-radius:9px;padding:16px 18px;margin-bottom:14px}
.tf-q{display:flex;gap:10px;align-items:flex-start;font-size:14px;line-height:1.75;color:#222;margin-bottom:12px}
.tf-buttons{display:flex;align-items:center;gap:9px}
.tf-btn{background:#fff;border:1.5px solid var(--ra);color:var(--ra);border-radius:6px;
  padding:5px 20px;font-size:12.5px;font-weight:700;cursor:pointer;transition:.15s}
.tf-btn:hover:not(:disabled){background:var(--ra);color:#fff}
.tf-btn:disabled{opacity:.4;cursor:default}
.tf-verdict{font-size:12.5px;font-weight:700}
.tf-verdict.ok{color:#1a6b3c}
.tf-verdict.no{color:#c0392b}
.tf-reveal{display:none;margin-top:13px;padding-top:12px;border-top:1px dashed var(--border)}
.ans-label.tf-true{color:#1a6b3c}
.ans-label.tf-false{color:#c0392b}